An Equal Opportunity Provider and Employer

CENTER FOR VETERINARY BIOLOGICS NOTICE NO. 20-08

TO: Biologics Licensees, Permittees, and Applicants

Directors, Center for Veterinary Biologics

Veterinary Services Leadership Team

American Veterinary Medical Association

FROM: Byron Rippke

Director

SUBJECT: Update to Equine Parvovirus Extraneous Agent Testing 

Requirement for Equine-Origin Antibody, Antitoxin, Antivenin, 

Serum, and Plasma Biological Products Regulated by APHIS

I. PURPOSE

The purpose of this notice is to inform interested parties of updated testing and 

reporting requirements for donor horses and serials of Animal and Plant Health 

Inspection Service (APHIS)-regulated antibody, antitoxin, serum, and plasma

products of equine origin for freedom from equine parvovirus-hepatitis (EPV-H).

Additionally, this notice announces procedures for extending the implementation 

period of the testing requirements for donor horses and serials of APHIS-regulated 

products of equine origin for freedom from EPV-H. The implementation will now be 

extended through April 30, 2021, to allow firms to comply due to unforeseen events 

related to the COVID-19 global pandemic.

Further, this notice informs interested parties that APHIS-regulated products derived 

from donor horses includes antivenin biological products regulated by APHIS. The 

labeling requirements, as stated in the Center for Veterinary Biologics (CVB) Notice 

19-03, will also apply to antivenin products of equine origin.

II. BACKGROUND

CVB Notice 19-03, published April 5, 2019, informed permittees and licensees of 

new labeling requirements for equine donor horse products. Additionally, the notice 

required that donor herds and serials of APHIS-regulated equine origin antibody,

antitoxin, serum, or plasma biological products be tested for EPV-H by methods 

acceptable to APHIS. The labeling requirements were to be met within 6 months of 

publication of the notice, while the testing requirements were to be met within 18 

months of the publication date. The testing requirement was implemented based on 

published research describing EPV-H as a probable cause of equine serum 

hepatitis 1-4

. An additional research study has been published5 indicating that the 

virus is present in, and can be spread by, administration of equine serum and/or 

Animal and Plant

Health Inspection

Service

Veterinary Services

Center for Veterinary 

Biologics

1920 Dayton Avenue

PO Box 844

Ames, IA 50010

(515) 337-6100
CENTER FOR VETERINARY BIOLOGICS NOTICE NO. 20-08

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 An Equal Opportunity Provider and Employer

plasma. The presence of the EPV-H in licensed veterinary biologicals poses a newly 

identified and unacceptable risk, requiring regulatory action. 

III. ACTION

A. ASSAY TESTING AGAINST EPV-H

EPV-H must be detected by an assay acceptable to APHIS. Licensees and permittees may 

develop an assay to detect EPV-H or use a contract laboratory for testing. Licensees and 

permittees should contact CVB regarding their testing preference prior to initiation of 

testing.

For licensees and permittees that will develop an assay, the assay must be validated, and

the limit of detection for the assay must be established. Interested parties must also 

satisfactorily complete testing of a quality assessment panel available from CVB. Upon 

satisfactory acceptance of the assay validation data and quality assessment panel results 

by CVB, the assay may be used for testing donor horses and final product serials.

B. Update of the Outline of Production (OP)

1. After CVB acceptance of the validation data and quality assessment panel results, 

Section I.B.1 of the OP must be revised to include annual EPV-H testing and 

testing of replacement donor horses.

2. Section V.B.1 of the OP must be revised to include serial testing of final product.

Include the following: name of laboratory performing the testing; assay test 

procedure; validity criteria for testing; and acceptance criteria for a satisfactory 

test including conditions for retesting. A Special Outline may be used to 

document the conduct of an assay performed by the licensee or permittee.

IV. IMPLEMENTATION/ APPLICABILITY

Product labeling per CVB Notice 19-03 and Outlines of Production, Sections I.B and V.B 

must be in compliance by April 30, 2021.

V. REFERENCES

1. Divers TJ, Tennant BC, Kumar A, McDonough S, Cullen J, Bhuva N, et al. New 

Parvovirus Associated with Serum Hepatitis in Horses after Inoculation of Common 

Biological Product. Emerg Infect Dis. 2018; 24(2):303-310. 

2. Tomlinson JE, Tennant BC, Struzyna A, Mrad D, Browne N, Whelchel D, Johnson 

PJ, Jamieson C, Löhr CV, Bildfell R, McKenzie EC, Laverack M, Renshaw RW, 

Dubovi E, Kapoor A, Meirs RS, Belgrave R, Engiles J, Van de Walle GR, Divers TJ.

Viral testing of 10 cases of Theiler's disease and 37 in-contact horses in the absence 
CENTER FOR VETERINARY BIOLOGICS NOTICE NO. 20-08

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 An Equal Opportunity Provider and Employer

of equine biologic product administration: A prospective study (2014-2018). J Vet 

Intern Med. 2019: Jan;33(1) 258-265.

3. Tomlinson JE, Kapoor A, Kumar A, Tennant BC, Laverack MA, Beard L, Delph K, 

Davis E, Schott Ii H, Lascola K, Holbrook TC, Johnson P, Taylor SD, McKenzie E, 

Carter-Arnold J, Setlakwe E, Fultz L, Brakenhoff J, Ruby R, Trivedi S, Van de Walle 

GR, Renshaw RW, Dubovi EJ, Divers TJ. Viral testing of 18 consecutive cases of 

equine serum hepatitis: A prospective study (2014-2018). J Vet Intern Med. 2019: 

Jan;33(1) 251-257.

4. Chandriani, S., Skewes-Cox, P., Zhong, W., Ganem, D. E., Divers, T. J., Van 

Blaricum, A. J Kistler, A. L. (2013). Identification of a previously undescribed 

divergent virus from the Flaviviridae family in an outbreak of equine serum hepatitis. 

Proceedings of the National Academy of Sciences of the United States of America, 

110(15), E1407–E1415.

5. Tomlinson JE, Jager M, Struzyna A, Laverack M, Fortier LA, Dubovi E, Foil LD, 

Burbelo PD, Divers TJ, Van de Walle GR. Tropism, pathology, and transmission of 

equine parvovirus-hepatitis. Emerging Microbes & Infections. 2020: 9(1) 651-633